A sliding bearing for a machine shaft, in this example the rotor shaft of a pump assembly, is known for example from European Patent 0 771 957 B1. With this sliding bearing, a bearing bush is applied onto the actual shaft.
With such bearing arrangements, the bearing bush is manufactured of a suitable bearing material, for example bronze or ceramic, while the rotor shaft is usually a conventional steel component. In order to permit a torque transmission from the rotor shaft onto the bearing bush, and to center the bearing bush, it is known to profile the shaft and to design corresponding profiles in the bearing bush, which engage with the shaft with a positive (form) fit.
Bearing bushes of ceramic have the advantage that they are very wear-resistant; ceramic however reacts very sensitively to tensile stresses. The problem is the fact that the coefficients of thermal expansion of the shaft, which is manufactured of steel, and of the ceramic bearing bush are very different, which leads to undesirable tensile stresses in the ceramic and thus finally to damage of the ceramic bearing bush on heating.